The user-interface has become a significant and increasingly complex element of many wireless communication devices, such as cell phones, personal digital assistants, and the like. As its name implies, the “user-interface” provides a mechanism through which a user can interact with the device. As such, a user-interface typically includes aural, visual, and/or tactile components through which the device can receive input from a user and provide output to the user, as well as a set of underlying control logic that governs operation of the various input/output components.
In general, the user-interface of a wireless communication device will have various states, and the user-interface will transition from one state to another in response to the occurrence of various user-interface events, such as the user pressing certain buttons or speaking certain commands.
By way of example, the user-interface may have a default state in which a display screen presents graphical indications of time of day and signal strength. When a user presses a MENU button on a keypad, the user-interface may then transition to a main-menu state, in which the display screen presents a menu of actions, such as links that the user can select to invoke a phone book application, a messaging application, a web browser application, and the like. In turn, when a user selects a desired menu item, the user-interface may transition to a next state that defines an application-specific screen image or the like.
As another example, the user-interface may have a one state in which the user interface emits audible signals (e.g., ring tones or other alerts) in response to certain stimuli. When a user selects one or more designated menu items or engages one or more other user-interface components (e.g., mechanical switches, etc.), the user-interface may then transition to another state in which the user-interface emits inaudible (or less audible) signals (e.g., vibrations) in response to those stimuli. Other examples of user-interface states and state-transitions are known as well.
Given that the user-interface defines the functional layer through which paying consumers interact with wireless communication devices, the manufacturers and distributors of such devices have an interest in making sure that the user-interface works as desired. To verify this in practice, manufacturers or distributors typically conduct study groups, in which a group of users sit in a room and interact with their devices while study-administrators observe what the users are doing and how the devices are responding. Unfortunately, however, such studies can be expensive. Further, the studies are inherently limited in that they merely reflect user interaction in a simulated test environment rather than in a real-life use scenario, and so the studies do not represent how users would normally interact with their devices.